Gripping device

ABSTRACT

A DEVICE, AND METHOD OF MAKING THE SAME, FOR GRIPPING A LINEAR BODY WHEREIN A PLURALITY OF HELICALLY PERFORMED RESILIENT ELEMENTS ARE SECURED IN A SOCKET MEMBER BETWEEN A SLEEVE AND A CORE BY SWAGGING OR OTHER MECHAN-   ICAL ACTION. THE PERFORMED ELEMENTS PROJECT FROM THE SOCKET AND ARE DISPOSED TO WAPPINGLY ENGAGE A LINE.

S. N. SCHLEIN GRIPPING DEVICE Feb. 9; 11,971

4 Sheets-Sheet 1 Filed may is, 1968 v INVENTOR. Seymour N. Schlein BY.0. aw

S. 'N. SCHLEIN GRIPPING DEVICE Feb. 9, 1971 4 Sheets-Sheet 2 Filed Mayl6, 1968 INVENTOR. Seymour N. Schlein Feb. 9, 1971 s. N. SCHLYEIN FiledMay 16,. .1968

4 Sheets-Sheet S United States Patent U.S. Cl. 24-123 16 Claims ABSTRACTOF THE DISCLOSURE A device, and method of making the same, for grippinga linear body wherein a plurality of helically preformed resilientelements are secured in a socket member between a sleeve and a core byswaging or other mechanical action. The preformed elements project fromthe socket and are disposed to wrappingly engage a line.

This invention relates to gripping devices, and more particularly tofittings employing helically preformed resilient elements and a methodof making such fittings. In even more particular aspects, this inventionrelates to fittings and their method of manufacture wherein a pluralityof helically preformed elements are held in a socket between a sleevemember and a core member by mechanical action, such as a wedging or byswaging, and which helically preformed elements extend from the socketand are adapted to grippingly engage the end of a line. This inventionalso contemplates the provision of an improved support engaging devicefor fittings and more particularly to a self-locking type bail devicefor fittings.

There have been many prior art devices for gripping of linear bodies.Several of these devices have utilized sets of helically preformed rodsbent in the form of a hairpin and comprising a bight to engage thesupport and a pair of helically formed legs for wrappingly engaging andgripping the line to be dead ended. These devices or fittings have beenquite successful for many applications. However, in some instances theattachment devices of the anchoring structure are not always ideallysuited for the fittings. This often requires the use of extra hardwareitems, such as thimbles, bolts and plates, to adapt the attachment tothe fittings. Also with respect to larger sizes of the fittingsthreading of the fitting through an otherwise compatible attachment issometimes difiicult.

One of the outstanding advantages of the present in vention is that afitting can be provided which is compatible with many different types ofattachment devices of anchoring structures.

Another feature of the present invention is the provision of a supportengaging member on a line gripping device which support engaging memberis frictionally secured to the socket member by a cap which isselftightening under pressure.

These and other advantages will become apparent together with a fullerunderstanding of the invention by reference to the following descriptionand accompanying drawings in which:

FIG. 1 is a side elevational view of one embodiment of a swaged linegripping device according to this invention;

FIG. 2 is a longitudinal sectional view of the device of FIG. 1;

FIG. 3 is a sectional view taken on line 3-3 of FIG. 1;

FIG. 4 is a longitudinal sectional view of another embodiment of a linegripping device according to this invention;

FIG. 5 is a side elevational view, partially in section of anotherembodiment of this invention showing a swaged 3,561,071 Patented Feb. 9,1971 line gripping device having the cap and bail which are ready tosecure the fitting to a support member;

FIG. 6 is a side elevational view of the device of FIG. 5 assembledaround the support member;

FIG. 7 is a sectional view taken substantially along the plane of line7-7 of FIG. 6;

FIG. 8 is another embodiment of the device similar to that shown in FIG.6 assembled on a support member;

FIG. 9 is a sectional view taken substantially along the plane 9-9 ofFIG. 8;

FIG. 10 is a longitudinal sectional view of a device showing the use ofa separate sleeve member for metal flow;

FIG. 11 is a sectional view taken substantially along the plane 1111 ofFIG. 10;

FIGS. 12 and 13 are side elevational views partially in sectionrepresenting a method of expanding a hollow core member to provide thematerial flow for securing the helically preformed devices;

FIG. 14 is a sectional view taken substantially along the plane 14-14 ofFIG. 13; and

FIGS. 15 and 16 are side elevational views, partially in section,showing the formation of a gripping device wherein the rods are held bywedging action.

Briefly, the present invention contemplates a line gripping devicewherein a plurality of preformed helical elements are mechanicallysecured between a sleeve memher and a core member to provide a socketedfitting. The helically preformed elements and socket in which theelements are secured will withstand a pulling force thereon exerted by aline gripped by the helically preformed elements. The invention alsocontemplates the provision of a support engaging device which will beself-tightening under pressure of a gripped line.

Referring now the drawings and for the present to FIGS. 1 through 3, oneembodiment of a swaged socketed dead end fitting according to thisinvention is shown. In this embodiment, a clevis member 10 is providedwhich has a hollow sleeve portion 12 and a pair of arms 14 and 15defining a bifurcated end. A clevis pin 16 is pro- -vided to passthrough apertures 17 and 18 formed in arms 14 and 15 for securing theclevis member to a support.

A plurality of resilient elements 20 are provided which are helicallypreformed to substantially conform to each other with respect to pitchlength and hand of lay. The resilient elements 20 are assembled in a setaround a core 22 and then inserted within the sleeve portion 12 of theclevis member 10. When the core 22 with the resilient elements 20wrapped therearound is inserted in this telescoping relationship withthe sleeve, the sleeve portion 12 is mechanically worked, preferably byswaging, to cause a metal flow to secure the resilient elements 20between the sleeve 12 and the core 22. This provides a socketed grippingdevice wherein a portion of resilient elements 20 are firmly gripped inthe socket and the remaining portion of the elements project therefrom.The elements have a common central axis and are disposed to wrappinglyengage a line L as shown in FIG. 2.

The core 22 serves several functions in this device. First, it providesa support for the helically preformed elements during the swagingoperation to permit the flow of material. The core also serves thefunction of allowing the resilient elements to be assembled and arrangedin a proper fashion and insreted within the sleeve so that the elementsare properly arranged to perform the gripping function.

As shown in FIGS. 1 through 3, the core is longer in length than thesleeve 12 and extends beyond both the front end and the rear end of thesleeve portion 12. The extending portions serve to prevent the markingor nicking of the resilient elements 20 during the swaging operationwhich would occur if the core terminated at or close to the end of thesleeve 12. Nicking or scoring can materially weaken the helicallyreformed elements and contribute to an early failure thereof. Bylengthening the core to permit it to extend beyond the ends of thesleeve member 12, sharp corners, which could cause nicks, are eliminatedin the region around the sleeve where force is applied during swaging.Also the end of the sleeve 12 is chamfered as shown to reduce the chanceof nicking.

The portion of the core extending forwardly (i.e. toward the portion ofthe elements which are to grip the line) provides a stop surface orabutment for the line to be gripped within the helically preformedelements.

Referring now to FIG. 4, a longitudinal sectional view of another typeof swaged socket fitting is shown. In this embodiment a socket member110 is provided having a hollow sleeve portion 112 at one end thereofand a threaded opposite end portion 113 extending therefrom. Thethreaded end portion 113 is adapted to threadably engage one end of aturnbuckle 119. The end of the sleeve member 112 is rounded or chamferedat 123, as in the previous embodiment. A plurality of helicallypreformed resilient elements 20, similar to those shown in FIGS. 1through 3, are wrapped around a core 122 which has a configurationsimilar to the core shown in FIGS. 1 through 3. This core, with theelements 20 wrapped therearound, is inserted within the hollow sleeveportion 112. In this embodiment, a resilient O-ring 124 is providedwhich surrounds the elements 20 Within the sleeve portion 112. This ringacts to further prevent nicking of the elements 20. Also, this ring willact, to some extent, as a moisture barrier. In this embodiment, as inthe previous embodiment, the sleeve portion 112 is swaged or otherwisemechanically worked to cause a mechanical fiow of material. This willsecure the ends of elements 20 between the sleeve portion 112 and thecore member 122 and they will extend therefrom for engagement with aline.

FIGS. 5 through 9 show two other embodiments of this inventionincorporating the feature of detachable bails for securing the line to asupport member.

Referring now to FIGS. 5 through 7, one particular embodiment of thistype device incorporating a detachable support securing means in theform of a bail and lock cap is shown. FIG. 5 shows the components of thedevice in a position ready for assembling to form a device which gripsthe end of a line. The device includes a socket member 210 which iscomprised of a hollow sleeve member 212 Which has been swaged over aplurality of helically preformed elements wrapped around a core 222 andinserted within the sleeve member 212. After the socket has been formeda cap member 230 is provided which is slipped over the end of thehelically preformed elements 20 and pushed up to near the end of thesleeve 212, as shown in FIG. 5.

Upon assembly the ends of the helically preformed elements 20 arewrapped around the end of the line as shown in FIG. 5 and a bail member232 is wrapped around a support S to which the socket 210 is to besecured. As can be seen, the outside surface of the sleeve 212 tapersfrom a smaller diameter adjacent the front end 215 thereof to a largediameter at the back end 217 thereof. The legs of the bail 232 areplacedadjacent to the tapering outer surface of the sleeve member 12 andthe cap 230 is pushed up the sleeve until it engages the legs of thebail member 230'. This position is shown in FIGS. 6 and 7.

As can be seen in FIG. 7, the cap member 230 has a central opening 234which is generally oval in shape with the elongated portion of the ovalbeing adapted to overlay the legs of the bail member 232. As the capmember 230 is pushed along the sleeve member 212 from the rear thereof,the diameter of the sleeve member 212 enlarges which causes the insidesurface 234 of the cap 230 to frictionally engage the legs of the bailmember 232. The farther the cap is pushed, the more force will beexerted against the legs of the bail member 232. Thus, as can be seen inFIG. 6, when a tension force is applied to socket member 210, tending topull it in a direction away from the support S, a force will urge thecap member farther along the sleeve 212 thus increasing the holdingforce exerted by the cap member 230 on the bail member. In the preferredembodiment, the internal opening 234 of cap member 230 also tapers fromfront end 231 to the rear end 233 which taper substantially correspondsto the taper of the sleeve 212. By having complimentary tapers in thismanner, a gripping or holding force will be exerted along the entirelength of the legs of the bail member 232 which are confined between thecap member 230 and the sleeve 212.

Referring now to FIGS. 8 and 9', another embodiment of a socketed deviceis shown. In this embodiment a sleeve member 212 is provided which isgenerally barrel shaped, i.e., tapering from a center of a largediameter to both ends of a smaller diameter. The helically preformedmembers 20* are swaged over a core 322 within the sleeve 312 as in theprevious embodiment. However, in this embodiment a cap member 330 has acentral opening which is generally circular in cross-section with a pairof relieved or cut-out portions 331 on opposite sides thereof. The bailmember 332 is comprised of a pair of bent wires which are adapted to bereceived within the cut-out portions 331 in the cap. The movement of thecap in 330 will lock the bail member 332 securely against the sleeve 312in a similar manner as described in conjunction with FIGS. 5 through 7.Again in this embodiment, the internal opening 334 of the cap has ataper substantially complimentary to the taper of the outer surface ofthe sleeve 312 from the center to one end. The barrel shape of thesleeve 312 provides some relief for the bail i.e., it does not bearagainst the sleeve past the mid portion thereof, this shape also permitsthe helical elements to be inserted into either end.

In the manufacture of the devices as described above, a hollow sleeveportion has been provided which is directly swaged over the helicallypreformed elements 20 as they are assembled on a core. One of therequirements for the successful formation of a socket is that there besufiicient metal flow to securely bond the helically preformed elementsand prevent them from pulling out. Thus, to obtain a good metal flow arelatively soft material, such as a mild steel is desirable. However,for certain applications it may be desirable to have a socket which isstronger than mild steel. FIGS. 10 and 11 show, somewhatdiagrammatically, the use of a relatively tough alloy outer sleeve 412into which is inserted a liner 413 of mild annealed steel or some othersofter material. This ring 413 surrounds the ends of the helicallypreformed elements 20 which are wrapped around a core 422 as in theprevious embodiments. When the outer sleeve 412 is swaged, themechanical force pressing inwardly thereon causes the inner ring 413 tocompress and metal flow thereof will take place bonding the helicallyformed ele ments 4:20 around the core 422. Since the ring 413 is of asofter and more malleable steel, this ring will be deformed to a greaterextent than would a ring of alloy steel, thereby increasing the bondingor holding power. This flowing action is shown somewhat diagrammaticallyin FIG. 11. This same result can be achieved by selectively softeningthe inner portion of an otherwise harder sleeve member, such as byselective annealing or decarbonization.

Referring now to FIGS. 12 through 14, a method of providing a bondedsocketed device is shown wherein the metal is caused to flow bymechanical force other than swaging. This embodiment allows a sleevemember of alloy steel of greater strength to be used while obtaining agood flow of material for a strong bonded socket. A

hollow sleeve member 512 is provided. The helically preformed elements20 are wrapped on a hollow core member 522. The core member 522 is madeof a malleable material such as annealed mild steel. A plug member 515is shown which is adapted to be inserted into the hollow core 522. FIG.12 shows the plug in a position to be inserted.

The plug 515 has one end 517 which is rounded and tapered with adiameter slightly smaller than the internal diameter of the core 522.(This taper is exaggerated in the drawing for purpose of illustration.)The remainder of the plug has a diameter slightly larger than theinternal diameter of the core 522. With the sleeve 512 contained in thejig or fixture (as shown diagrammatically in FIG. 12) an axial forceapplied to the plug member 515, designated by the force Vector P, willdrive the plug into the core 522. Preferbly the plug is hardened, or atleast case hardened, and the hollow core 522 is relatively soft. Thisforce driving the plug into the core will cause the relatively softmaterial of the core to expand and flow to some degree around thehelically preformed elements 20 to form a secure bond.

This plug member 515 preferably is left in the core 522, as shown inFIG. 13, to prevent the core from collapsing or giving under stress andprovide a firm solid base to solidly maintain the helically preformedmembers bonded between the core and the sleeve.

Although swaging and expansion type mechanical forces have beendescribed in conjunction with forming this type of socket grippingdevice, it is to be understood that various other types of mechanicalforce can be applied to cause material movement to bond helically formedelements to a socket. Any type of mechanical force and socket and coreconfiguration which Will provide for such material movement or flow canbe used in practicing this invention.

In the various methods described in forming the socketed dead endaccording to this invention, the helically preformed elements have beenwrapped around the core and inserted into the hollow socket member. Ithas been found that if too much clearance is allowed between theinternal surface of the sleeve and the external surfaces of thehelically preformed elements, two rather serious disadvantages areencountered. First, it is difficult to maintain the elements wrapped onthe core in the proper position during the swaging operation; andsecond, an excessive amount of force is needed just to close thediameter of the socket down far enough until it starts to engage theexternal surfaces of the helically formed elements before any bondingaction takes place. On the other hand, reducing this clearance makes itdifiicult to insert the core 'with the helically formed elements wrappedthereon into the hollow sleeve. It has been found, therefore, that it ispreferable in practicing the invention to select the interior diameterof the sleeve to be equal to, or just slightly smaller than the outsidediameter of the helically formed elements wrapped upon on the core andthen heat the sleeve member so that it expands to a diameter larger thanthe external diameter of the helically formed elements wrapped aroundthe core. The sleeve in the heated condition can then easily he slippedover the helically formed elements. This will tightly hold the elementsin place for the swaging or other mechanical working operation whichwill ultimately cause the bond. In the case of the method described withreference to FIGS. and 11, both the ring and the sleeve may be heatedwith good results.

Referring now to FIGS. and 16, still another embodiment of the grippingdevice according to this invention is shown. In this embodiment thehelically preformed rods are secured between the sleeve member and thecore member by a wedging action produced by the relationship of thesemembers as opposed to a flow of metal as in the previously describedembodiments.

In this embodiment the sleeve member 612 takes the form of a sockethaving a generally frusto-conically shaped interior cavity 613. The plugor core 615 has a generally frusto-conically end portion 616 and atongue or projection portion 617.

In order to form the dead end, the helically formed rods 20 are wrappedaround the plug 615 and their ends inserted through the end opening 619in the socket as shown in FIG. 15. The plug 615 with the rods 20 wrappedthereon is then wedged firmly into the interior cavity 613 of the socket612. The complimentary taper between the cavity 613 and the end portion616 of the plug 615 will cause a wedging action to take place, wedgingthe rods 20 between the socket 612 and the core 615. The tighter theline pulls against the rods 20, the tighter will be the wedging actiondeveloped within the sleeve 612. This wedging action will firmly seatthe rods 20 between the core 615 and the sleeve 612 providing a firmgripping action which will effectively grip the line being dead ended.

In illustrating the various embodiments of the invention, the elementshave been helically preformed throughout their entire length. Thehelical formation is for the purpose of allowing the elements togrippingly engage a line and hence those portions of the elements whichextend from the socket must be so formed so that they can grippinglyengage a line. It is also desirable that the ends of the elements whichare contained within the sleeve also be helically preformed, but it isnot essential. The helical formation has a certain amount of resistancetoward any tendency of the elements to pull loose from the socket andthus this type of helical formation throughout the entire length of theelements is desired, but it is not absolutely necessary.

Also, as is well known in the art, some type of grip enhancing materialmay be used on the rods 20. This may take the form of alumina, or othergrit adhesively applied to the rods.

While several embodiments of this invention have been shown anddescribed, various adaptations and modifications may be made thereofwithout departing from the scope of the invention as defined in theappended claims.

What is claimed is:

1. A device for gripping a linear body comprising a plurality ofresilient members having first and second end portions, at least thefirst end portions having been helically formed to a self sustaininghelical configuration which configuration will return after deformationwithin the elastic limit and substantially conforming to each other withrespect to pitch length, internal diameter, and hand of lay, socketmeans including a sleeve member and a core member retaining said secondend portions of said elements, said sleeve member and said core memberbeing arranged in telescoping relationship with the second end portionsof said elements being secured therebetween, said core member extendingbeyond the said sleeve member and terminating within the confines of theresilient members, at least a portion of said core being engaged by saidresilient elements and said first end portions of said resilient membershaving a common internal diameter and being free of interwoven portionswith a portion of said second end portions extending a substantialdistance beyond said extending core to wrappingly engage a linear body.

2. The device of claim 1 wherein said elements are wedged between saidsleeve and core members.

3. The device of claim 2 wherein said sleeve and said core membersincludes frusto-conical surface area engaging said elements betweenthem.

4. The device of claim 1 wherein said sleeve member flares outwardly atthe end thereof at which said helically formed elements enter.

5. The device of claim 1 wherein said sleeve member has means forattachment to a support.

6. The device of claim 5 wherein said means for attachment to a supportincludes a clevis pin and means to detachably secure said clevis pin.

7. The combination of claim 5 wherein said means for an attachment to asupport includes threaded means adapted to threadably engage a pinbuckle.

8. The device of claim 1 wherein said elements are secured between saidmembers by material displaced from one of said members.

' 9. The device of claim 8 wherein a resilient packing member isprovided between said elements and said sleeve member.

10. The device of claim 8 wherein the material flow is at least in partfrom the sleeve member.

11. The device of claim 8 wherein the sleeve member includes arelatively soft metal inner portion adjacent and surrounding saidhelical preformed elements.

12. The device of claim 11 wherein said inner portion is a separateelement.

13. The device of claim 8 wherein a metal displaced is at least partlyfrom said core member.

14. The device of claim 13 wherein said core member includes a hollowportion, said hollow core portion having been expanded to cause metal toflow for said bondmg.

15. The combination of claim 14 wherein a plug is carried within saidhollow portion of said core member.

16. The device of claim 1 wherein the portion of the elements betweenthe sleeve member and the core member are helically formed.

References Cited UNITED STATES PATENTS 814,472 3/1906 Noonan 24123.5UX1,440,504 1/1923 Snow 24-126.2UX 1,466,127 8/1923 Gottschalt 24-122.61,973,322 9/1934 Staples 24-122.6X 2,279,237 4/1942 Kellems 24 123.5UX2,664,609 1/1954 Kellems 24-1'23.5UX 2,698,150 12/1954 Di ,Palma 24123.5UX 2,766,501 10/1956 Kellems 24-123.5UX 3,219,298 11/1965 Ruhlman248-63 FOREIGN PATENTS 9,689 6/1890 Great Britain 24 126.2 156,3371/1921 Great Britain 24 126.2

BERNARD A. GELAK, Primary Examiner US. Cl. X.R.

